Bioinformatický seminár

Tue 25 Oct. 2011, 17:20
I-9

Title: Tuller et al. An evolutionarily conserved mechanism for controlling the efficiency of protein translation
Speaker: Katka Juríková

Recent years have seen intensive progress in measuring protein
translation. However, the contributions of coding sequences to the
efficiency of the process remain unclear. Here, we identify a universally
conserved profile of translation efficiency along mRNAs computed based on
adaptation between coding sequences and the tRNA pool. In this profile,
the first approximately 30-50 codons are, on average, translated with a
low efficiency. Additionally, in eukaryotes, the last approximately 50
codons show the highest efficiency over the full coding sequence. The
profile accurately predicts position-dependent ribosomal density along
yeast genes. These data suggest that translation speed and, as a
consequence, ribosomal density are encoded by coding sequences and the
tRNA pool. We suggest that the slow \"ramp\" at the beginning of mRNAs
serves as a late stage of translation initiation, forming an optimal and
robust means to reduce ribosomal traffic jams, thus minimizing the cost of
protein expression.